Socket assembly for air-cooled tubes



Jan. 4, 1949. E. H. POTTER sbCKET IiSSEMBLY FQR AIRCOOLED TUBES FiledMarch 31, 1948 iINTOR ELVIN .1 run I ATTORNEY Patented Jan. 4, 1949SOCKET ASSEMBLY FOR AIR-COOLED TUBES Elvin H. Potter, Oollingswood, N.Jl, assignor to Radio Corporation of America, a corporation of DelawareApplication March 31, 1948, Serial No. 18,173

This invention relates to improvements in supports for air-cooledelectron tubes and has for its principal object to provide a rapidlydetachable, substantially leak-proof, socket assembly of low electricalimpedance for air-cooled electron tubes of the so-called-lighthousevariety.

The invention will be described in connection with the accompanyingdrawing, wherein:

Fig. 1 is an elevational view of an air-cooled tube and socket assemblyconstructed in accordance with the principle of the invention,

Fig. 2 is an elevational View of the conduit portion of the assemblyshowing the manner in which the threaded base of the tube is supportedupon a slidable sleeve-portion of the cooling conduit,

Fig. 3 is a sectional view taken on the line III-III of Fig. 1 showingtwo coupling devices within the slidable sleeve, one for connecting thesleeve to the conduit and the other for holding the tube in the sleeve,

Fig. 4 is an elevational view, partly in section, taken on the lineIV-IV of Fig. 3 showing the interior of the sleeve and the manner inwhich the coupling devices of Fig. 3 operate, and

Fig. 5 is a view in perspective of the interior of the sleeve, with thetube removed, showing the contour of and relative arrangement of thecouplingdevices therein.

The electron tube T, to which the invention is here applied, is of theair-cooled lighthouse variety (JAN and RCA type No. 4033) and is shownmounted, up-side-down, upon a tri-part supporting assembly which mayhere briefly be described as comprising: (a) an upper conduit, part 0,which supplies current to the anode terminal I of the tube and a streamof air to its cooling jacket 2, (b) an intermediate annular pedestal,part P, upon which the flange-like grid connector 3 of the tube isresiliently supported and (c) a lower socket in the form of atransmission line, part L, through which electrical energy is suppliedto the cathode cap 4 and filament prong 5 of the tube. I

As is conventional in tubes of the type described, the cooling jacket 2comprises a multiplicity of metal fins 2a which extend radially outwardfrom the anode 6 (see Fig. 4) and are bent over adjacent to their outerends into contact with the next adjacent fin to provide a multiplicityof open-ended channels 20 through which a cooling stream of air may bepassed from the base of the tube to a region adjacent to theglass-to-metal seal 1 which joins the anode to the bulbous glass portion8 from which the grid flange 3 projects. It will be observed that the 7Claims. (01. 250-275) upper ends of the fins 2a all terminate in thesame plane as the outer end of the internallythreaded anode terminal I,i. e. in the plane of the base of the tube, as indicated by thereference line 11-27 in Fig. 4.

The conduit 0 which supplies current to the anode 6, and through whichair flows to the cooling jacket 2, is here shown as comprising ahorizontally disposed portion I0, which will be understood to beconnected to a pump, not shown, and a shorter vertical section II whichhas aslidable sleeve I2 on its outer surface. The stationary pipe-likepieces I0 and II are rigidly secured to the underside of a stationarybase I3 as by an insulating stud I 4 disposed at the elbow of the pipe.

The dependent short arm II of the conduit C is provided with twovertically extending oppositely located bayonet slots I5, I5 which serveto accommodate a complementary bayonet pin I6 which is mountd, in amanner later described, within the vertically movable sleeve I2. Each ofthe bayonet slots I5, I5 terminates at itslower end in a laterallyextending cut-out portion II within which the bayonet pin I6 is adaptedto be seated upon rotation of the sleeve I2 while the sleeve is in itsextended or down position. As is shown in Fig. 4, the lower corners ofthe bayonet slots which lie opposite to the lateral slot portions I! arecut away as indicated at H in order to guide the bayonet pin I B (andits support I8, later described) into the vertical portion I5 I5) of thesaid slots when it is desired to raise the sleeve I2 on the stationaryvertical section I I of the conduit.

As above mentioned, the sleeve I2 is supported for slidable ortelescopic movement on and with respect to the stationary dependent partI I of the air-supply conduit. When, as in the instant case, the saidconduit has a horizontally extending part II), that portion of thesleeve I2 which lies beneath the said horizontal part II) may be cutaway in a U-shape pattern, as shown at I 2u (see Figs. 2 and 5), so thatthe said part ID will not interfere with the upward movement of thesleeve I2.

As shown more clearly in Figs. 3, 4 and 5 the sleeve I2 contains a metalslab or plate I8 mounted with its major faces m arranged parallel to thevertical axis of the sleeve so that its presence will not appreciablyimpede the flow of air therethrough. The plate I8 is thin enough to bereceived Within the vertical portion of the bayonet slots I5 in thedependent stationary part I II of the conduitC and is soldered orotherwise rigidly tained in suitable holes on opposite sides of the,

vertical axis of the plate. The pin is retained in its groove by crimps20 on the top edges of the groove.

are cut away to permit the pin to be depressed It will be observed uponinspection of. Fig. 5 that, as indicated at 2| the corners of the. platel8 beneath the ends of the bayonet pin l5;

4 socket 33 for the filament prong 5 is free to slide on a flange 34 onthe inner surface of the outer conductor and thus to compensate for anyeccentricity in the relative alignment of the finament prong 5 withrespect to the cathode cap 4.

From the foregoing it will be apparent that the invention provides arapidly detachable, substantially leak-proof, socket assembly of lowelectrical impedance for air-cooled electron tubes, and one which lendsitself readily for use in the mounting of electron tubes of thelighthouse springs l9 when the sleeve is moved to a position whereat theends of the bayonet pin are seated within the laterally extendingportions ll of the bayonet slot in the dependent stationary part I! ofthe conduit.

. An externally threaded stud 22 which is adapted to be received withinthe internally threaded anode terminal I serves to attach the tube T tothe sleeve I2. It will be observed that when the tube is screwed-up onthe said stud, the periph-r ery of the cooling jacket 2 lies contiguouswith the lower edge of the sleeve. In order to provide a substantiallyair-tight fit of low electrical impedance between these circularabutting edges of the cooling jacket and sleeve the stud 22 is somewhatloosely attached to the plate 18, as by a loosely fitting yoke 23 andscrew 24, so that the tube may tilt slightly when it is screwed-up onthe nut in any direction required to provide a selfleveling contactbetweenthe said abutting edges. Because of the inclusion in the mountingassembly of the pedestal P for the grid flange 3 of the tube it isapparent that the tube can be entered into the pedestal and screwed upon the stud 22 only when the sleeve is in its raised position, as shownin Fig. 2.

The pedestal P ior the grid flange 3 of the tube T comprises a metalshelf 25 having a hole 25a therein of a diameter sufficiently large topermit the tube to be tilted therein and, suspended from the said shelfas on spacers 26, an apertured panel 21 containing a number ofelectrical contact elements in the form of spring fingers 2'8 arrangedin circumferentially spaced relation about the periphery of the aperturein a position to engage the underside of the grid-flange 3. When, as isusually the case, the grid is operated at ground potential the terminals28 may be connected to the metal shelf 25, or they may be insulatedtherefrom (as in the drawing) in the event that a D. C. bias is to beapplied tothe grid. It should be noted that the springs 19 which exertan upward biasing force on the bayonet pin IB also exert a downwardforce upon the upper end of the cooling jacket 2 and this downwardlydirected force is transmitted through the envelope of the tube to thegrid flange 3 which is thus urged into intimate contact with the springfingers 28. I

The transmission line Lin whose open-end the cathode cap 4 and filamentterminal 5 are received terminates in a multiplicity of spring fingers3B which grip the cap 4 tightly even though there may be minorinaccuracies in the alignment of the vertical axes of the transmissionline L variety.

What is claimed is:

1. A support for an electron tube of the type provided with an anodeterminal on one end, an open-ended cooling jacket adj acenttosaid endand a radially extending flange-like grid-like terminal intermediatesaid jacket. and the other end of said tube, said support comprising ahollow sleeve to which said tube is adapted to be removably secured withthe leading end of said sleeve in contact with the periphery of saidcooling: jacket and the interior of said sleeve in flow communicationwith the interior of said cooling jacket, a stationary air-supplyconduit upon which said sleeve is mounted for axial movement, astationary pedestal mounted in spaced relation with respect to saidconduit and sleeve and having an aperture therein through which saidother end of said tube is adapted to be passed when said sleeve is movedinwardly on said conduit and upon which said grid flange is adapted tobe seatedupon movement of said sleeve in the return direction.

2. The invention as set forth in claim 1 and wherein spring meansaremounted upon said pedestal for applying a biasing force to saidgridflange in the direction of said stationary section of said conduit.

and the tube T resulting from tilting of the grid 3. A support for anelectron tube of the type provided with an anode terminal on one end, acooling jacket adjacent to said end and a radially extending flange-likegrid terminal intermediate said jacket and the other end of said tube,said support comprising a hollow sleeve to which said tube is adapted tobe removably secured with the leading end of said sleeve in contact withthe periphery of said cooling jacket and the interior of said sleeve inflow communication with the interior of said cooling jacket, said sleevecontaining a coupling member'for said anode electrode and a bayonet pin;a stationary conduit section upon which said sleeve is adapted to bereceived and having an axially extending slot for accommodating saidbayonet pin upon movement of said sleeve in the axial direction uponsaid conduit section, said slot terminating at the free end of saidconduit section in a laterally extending portion within which said pinis adapted to be seated upon rotation of said sleeve on said conduit, astationary pedestal mounted in spaced relation with respect to said endof said stationary conduit and having an aperture therein through whichsaid other end of said tube is adapted to be passed when said sleeve ismoved in the direction of extension of said axial slot and upon whichsaid grid flange is adapted to be seated upon movement of said sleeve inthe return direction to a position whereat said bayonet pin is receivedwithin said laterally extending portion of said bayonet slot.

4. The invention as set forth in claim 3 and wherein said stationaryconduit section and said sleeve are .constituted of metal and comprise aconductive lead through which electrical energy 5 may be applied to saidanode terminal through the connector within said sleeve.

5. The invention as set forth in claim 3 and wherein spring means arehoused within said sleeve for biasing said bayonet pin into intimatecontact with an edge of said lateral extension of the bayonet slot insaid conduit section.

6. The invention as set forth in claim 3 and wherein said anode-terminalconnector is tiltably supported within said sleeve whereby when said 106 tube is connected to said connector the cooling jacket of said tube isself-leveling with :respect to the adjacent edge of said sleeve.

7. The invention as set forth in claim 3 and wherein resilient means arein register with said pedestal aperture for receiving and supportingsaid other end of said tube.

ELVIN H. POTTER.

No references cited.

